Stripping machines



Jan. 22, 1957 w. E. WALKER STRIPPING MACHINES 2 Sheets-Sheet 1 Filed July 20, 1953 l I I I IIE ll llullilFlLLll;

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INVENTOR WILLIAM E. WALKER By W, WM. x ATTORNEY Jan. 22, 1957 w. E. WALKER STRIPPING MACHINES 2 Sheets-Sheet 2 Filed July 20, 1953 nvvewron \Jl LUAM E. WALKER ATTORNEY 2,778,286 STRIPPING MACHINES William Edward Walker, Enfield, England Application July 20, 1953, Serial No. 369,167

14 Claims. (Cl. 93-36) This invention relates to stripping machines for stripping unwanted or waste material from cardboard and like material which has previously been cut and creased. The invention is chiefly useful in connection with cut and creased individual sheets but is also applicable when the cut and creased material is in continuous strip or web form.

Stripping machines in the past have been very expensive and inflexible. In one such machine one of a pair of driven rollers has secured in its surface pins which are located specially in accordance with the location of the unwanted material; the other roller, which, like the first is made of steel, has recesses cut out of the surface to receive the pins of the first roller. As will be appreciated, both rollers have to be made specially for stripping cut and creased material of any particular design and are useless when the design is changed; they are, therefore, used entirely for cut and creased material in strip or web form where the numbers of individual blanks to be made from the strip are very large, and justifies the large expense required for the stripping rollers.

When a small number of blanks are to be produced, it has been uneconomic to strip mechanically, and these are usually stripped by hand, a'process that is timewasting and costly. No machines to our knowledge have been devised for stripping economically small numbers of blanks.

An object of the invention is thus to provide stripping means that are readily adaptable for stripping blanks of differing design, little modification being required to alter the machine for use with one design to use with another.

A stripping machine according to the present invention comprises a pair of cooperating rollers between which the blanks are fed and means adapted to be secured on one roller for holding in any selected position pins for piercing the unwanted material, the other roller having a surface which is sufficiently stiff to ensure that the blanks are gripped between and drawn through the rollers but is penetratable by the pins at any desired point in at least a part of the surface. This machine can be used with blanks both in sheet form and in strip or web form.

Preferably, the holding means comprises a tympan securable to the surface of the pin-holding roller and formed by a thin metal sheet perforated at narrowly spaced regular intervals, the pins being insertable through any of the perforations.

The pin-receiving roller preferably has a surface consisting of a wire brush or engineers file-card. However, other materials may be used such as stiff sponge rubber into which the pins can penetrate without unduly damaging the material and which is stiff enough to cooperate with the pin-holding roller to grip and draw the blanks therebetween.

The invention will be more readily understood by way of example from the following description of a stripping nited States Patent 2,778,286 Patented Jan. 22, 1957 machine in accordance therewith, reference being made to the accompanying drawings, in which:

Figure 1 is a front view of the stripper;

Figure 2 is a section on the line II-II of Figure 1;

Figure 3 is a section on the line III-III of Figure 2, and

Figure 4 is a section similar to Figure 2 on an enlarged scale, showing a pin in position.

The stripper comprises two driven wooden rollers 12,

13 mounted one above the other at the delivery end of the blank cutting and creasing machine. The upper or pin-receivingroller 13 has its surface almost entirely covered by a length of engineers file-card or wire brush 14 which is arranged as shown in Figure 2 with the wires located pointed radially outwards. The lower or pinholding roller 12, on the other hand, carries a tympan of perforated metal sheet 15. Roller 12 has a sector 16 cut therefrom; to the walls of this sector are secured the ends of the sheet 15 with, beneath the sheet 15, a card underlay 17 and a paper backing sheet 18. The sheet 15 and the layers 17, 18 underneath are held in place by screws 19 threaded into holes in the roller 12. The sheet 15 is of 24 S. W. G. and the perforations therein are approximately 0.080 in diameter arranged in a square pattern of approximately A" pitch. Through selected perforations are passed, before the sheet is secured on the roller 12, pins 20, the heads of the pins being located on the inner side of the sheet 15 and accommodated in the underlay 17. The shanks of pins 20 thus project radially outwardly from the roller 12.

While the cutting and creasing machine is being prepared for a new job, the tympan 15 and the underlayers 17 and 18 are removed from roller 12 and pins 20 located in perforations in tympan 15 corresponding to the position of the waste or unwanted material in the new blanks. The tympan and underlayers are then replaced on the roller 12. Alternatively, a second tympan can .be prepared, during use of a first tympan, with, the pins in appropriate position for the next job. On change-over,

the second tympan is merely substituted on roller 12 for the firstwhich is stored for reuse it required.

The blank 21 which is fed from the cutting and creasing machine is seized in the bite of the rollers 12 and 13 and drawn therethrough, the separation of the rollers.

12, 13 being such that the blank is firmly caught by the surfaces thereof without unduly bending and damaging the file-card 14. During passage of the blank 21 through the rollers, the pins 20, which have been specially positioned for this purpose, pentrate the unwanted or waste parts 22 of the blank and hold those parts to the surface of tympan 15. The wanted parts 23 of the blank 21 on the other hand are not so held by pins 20 and move tangentially with respect to the rollers, being seized and removed by the pair of conveyor rollers 35.

To remove the unwanted material from the pins 20 after separation from the blank, a comb 24 is mounted adjacent the surface of the roller 12 beneath the bite of the rollers. The teeth 25 of the comb 24 are chamfered to edges located very near to the surface of the tympan 15 so as to enter between the unwanted material 22 and the tympan, and remove the unwanted material carrying at either end a cam roller 27. Cam rollers 27 travel in stationary cam tracks 28 located at each side of the roller 12. At spaced axial intervals in the roller 12 are radial slots 29, each opening at one end to the surface of roller 12 and at the other end to slot 25. These slots 29 are aligned with threaded holes 30 in the bar 26 and with holes in the tympan and underlayers 17, 18. According to the location of the wanted material 23 in the blank 21, plungers 31 are screwed into selected holes 30.

Cam tracks 28 are circular over the larger parts of their lengths and the plungers 31 are thereby held retracted within the roller 12 and do not foul the comb 24. However, when the plungers pass under the bite of the rollers, the cam tracks cause the plungers to project outwardly from the roller and the outer ends of the plungers to follow for a short distance a tangential and horizontal path with respect to the roller. The plungers 31 are selectively located to engage, when they project in this way, only the wanted parts of the blank and to cause these parts to be forced away from the tympan 15 so as to ensure that the leading edges are seized by the rollers 35. The cam track then causes the plungers 31 to retract before they reach the comb 24.

Where the speed of rollers 12, 13 is small, it may be found that the plungers 31 can be dispensed with. Alternatively, other means for pressing the wanted material away from the roller 12 may be used, such as sponge rubber pads located on the surface of the tympan 15 or spring fingers so mounted, the comb 24 being recessed to allow the pads or fingers to pass. The pads or fingers will force the wanted material away from the roller.

The rollers 12, 13 are driven through meshing gear wheels 33, 34 at the same peripheral speed. These gear wheels may be driven by the cutting and creasing machine or by an independent motor, although the former is preferred as synchronism is then more easily attained.

As has been explained, the configuration of pins 29 in tympan 15 can quickly be changed to suit varying designs of blank, merely by removing the tympan from the roller 12 and locating the pins in different perfora tions suited to the shape of the waste material of the new design. Similarly, the positioning of plungers 31 can be quickly altered to suit a new design of blank. By virtue of the nature of file-card 14- on roller 13, pins will be received by the upper roller 13, whatever their positions without undue damage to the file-card and accordingly the upper roller does not have to be altered at all when the blanks to be stripped are changed in design. Altogether, changeover of the stripper can be effected quickly and with ease.

I claim:

1. In a stripping machine for stripping cut blanks the combination of a first roller, a sheet detachably secured round said first roller and penetratable at any desired point by pins, and a plurality of headed pins inserted in said sheet at positions selected in accordance with the location of unwanted material in the blanks, the heads of said pins being located between said sheet and said first roller, and a second roller cooperating with said first roller and receiving in the surface thereof said pins as said rollers rotate.

2. In a stripping machine, the combination of a first roller, a perforated sheet detachably secured round said first roller, a plurality of headed pins receivable in any of the perforations of said sheet and inserted in perforations of said sheet selected to cause piercing of unwanted material by said pins, the heads of said pins being located between said sheet and said first roller, and a second roller cooperating with said first roller and receiving in the surface thereof said pins as said rollers rotate.

3. In a stripping machine for cut blanks in sheet form, the combination of a first roller, a uniformly and closely perforated sheet detachably secured round said first roller, a plurality of headed pins receivable in any of the perforations of said sheet and inserted in perforations selected in accordance with the location of unwanted material of said sheet blanks, the heads of said pins being located on the inner side of said sheet, means mounted on said first roller for urging outwardly from the surface of said first roller the leading edge of the wanted material, and a second roller cooperating with said first roller for feeding said sheet blanks therebetween.

4. In a stripping machine, the combination of a first roller, a sheet detachably secured to said roller and having uniform and closely spaced perforations therein, a plurality of headed pins receivable in any of said perforations and inserted in perforations selected in accordance with the location of unwanted material in blanks to be stripped, the heads of said pins being located on the inner side of said sheet, a second roller cooperating with said first roller for the feed of blanks therebetween, and a strip of wire brush secured to said second roller with the wires disposed radially outwardly from said second roller and receiving said pins of said first roller therebetween.

5. The combination according to claim 4, comprising also means on said first roller for urging outwardly from the surface of that roller the leading edge of the wanted material of said blanks as said wanted material comes between said rollers.

6. The combination according to claim 5, in which said means for urging outwardly the wanted material comprises a plurality of plungers suitably mounted in recesses in said first roller and means synchronized with the rotation of said first roller for urging the plungers outwardly when the leading edge of the blank passes between the rollers.

7. The combination according to claim 6, in which some or all of said plungers are removable from the rollers in accordance with the configuration of the wanted material of the blanks.

8. The combination according to claim 7, comprising also a bar into which said plungers are screwable and which is arranged transversally within said first roller and radially movable therein, the ends of the bar projecting from the roller, cam rollers carried on the projecting ends of said bar, and cam tracks cooperating with said cam rollers and arranged to cause outward movement of the bar and plungers at the desired time in the rotation of said first roller, but at other times to hold the bar and plungers retracted.

9. In a stripping machine for cut blanks in sheet form, the combination comprising a first roller, a sheet detachably secured round said first roller and penetratable at any desired point by pins, a plurality of headed pins inserted in said sheet at positions selected in accordance with the location of unwanted material in the blanks, the heads of said pins being located between said sheet and said first roller, means mounted on said first roller for urging outwardly from the surface of said first roller the leading edge of the wanted material, and a second roller co-operating with said first roller for feeding said sheet blanks therebetween and receiving in the surface thereof said pins as said rollers rotate.

10. In a stripping machine for out blanks in sheet form, the combination comprising a first roller, a sheet detachably secured round said first roller and penetratable at any desired point by pins, a plurality of headed pins inserted in said sheet at positions selected in accordance with the location of unwanted material in the blanks, the heads of the said pins being located between said sheet and said first roller, a plurality of plungers mounted in recesses in said first roller, means synchronised with the rotation of said roller for urging said plungers outwards at a prescribed position of said roller in order to urge outwardly from the surface of said first rollerthe leading edge of the wanted material, and a second roller co-operating with said first roller for feeding said sheet blanks therebetween and receiving in the surface thereof said pins as said rollers rotate.

11. In a stripping machine for cut blanks in sheet form, the combination comprising a first roller, a sheet detachably secured round said first roller and penetratable at any desired point by pins, a plurality of headed pins inserted in said sheet at positions selected in accordance with the location of unwanted material in the blanks, the heads of said pins being located between said sheet and said first roller, and a second roller co-operating with said first roller for the feed of blanks therebetween, said second roller having secured thereto a strip of wire brush to receive said pins of said roller between the wires thereof.

12. In a stripping machine for cut blanks in sheet form, the combination comprising a first roller, a sheet detachably secured round said first roller and penetratable at any desirable point by pins, a plurality of headed pins inserted in said sheet at positions selected in accordance with the location of unwanted material in the blanks, the heads of said pins being located between said sheet and said first roller, a second roller co-operating with said first roller for the feed of blanks therebetween, a strip of wire brush secured to said roller with the wires disposed radially outwardly from said second roller and receiving said pins of said first roller therebetween, and means on said first roller for urging outwardly from the surface of that roller the leading edge of the wanted material of said blanks as said wanted material comes material in the blanks whereby said unwanted material is impaled and retained by said pins, the heads of said pins being located between said sheet and said first'roller and said second roller having a surface penetratable by said pins as said rollers rotate, means for urging outwardly from the surface of said first roller the leading edge of the Wanted material as said wanted material comes between said rollers, and means forremoving from said pins unwanted materials impaled on said pins.

14. In a stripping machine for cut blanks in sheet form, the combination comprising a first roller, a second roller co-operating with said first roller for feeding said blanks therebetween, a sheet detachably secured round said first roller and penetratablc at any desired point by pins, a

plurality of headed pins inserted in said sheets at positions selected in accordance with the location of unwanted material in the blanks whereby said unwanted material is impaled and retained by said pins, the heads of said pins being located between said sheet and said first roller, said second roller having a surface comprising outwardly projecting wires which are penetratable by said pins but which co-operate with said firs-t roller to feed said blanks, means for urging outwardly from the surface of said first roller the leading edge of the wanted material as said wanted material comes between said rollers, and means for removing from said pins unwanted materials impaled on said pins.

References Cited in the file of this patent UNITED STATES PATENTS 754,253 Stewart Mar. 8, 1904 1,462,369 Lowe July 17, 1923 1,970,396 Scherer Aug. 14, 1934 1,983,708 Ruble Dec. 11, 1934 2,479,521 Stewart Aug. 16, 1949 2,647,446 Kane Aug. 4, 1953 

